Move while stunned or locked down

I've started seeing this thing recently, where if I get rooted, stunned or locked down in any way in the game, I slightly move foreward a bit, and then get pulled back. One of my friends just informed me that he's experienced his as well, for example when using zhonya's. The way I see it, the movement is not actually happening, and the characters hitbox stays at the place it gets stunned.

This is a very annoying bug, fix it, Riot, if you feel like it. I dont actually expect the fix to come any time soon, as minor glitches and bugs like this are unnoticed or maybe intentionally ignored